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Old 1-May-2015, 3:02 PM   #1
Jason l
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What's your favorite high gain pree amp

just want to know who has good results with high gain amps for ota TV it seems to be getting more and more limited as the market changes. I'm stuck using an old discontinued winegard. It just WORKS! Any one have luck with newer amps?
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Old 2-May-2015, 4:17 PM   #2
GroundUrMast
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You're right, the options are getting fewer.

As a caution to those unfamiliar with the appropriate application of amplifiers in an OTA TV antenna system; In many cases an amplifier is not needed, and the use of of one may result in less reliable reception due to overloading. This is especially true of high gain amplifiers. Channel Master states the following on their web site, "An ideal scenario for the Titan 2 High Gain Preamplifier is an application where ALL broadcast towers are 80+ miles from the antenna location and a splitter is used to distribute to multiple televisions. A single high-power signal from closer proximity may cause over-amplification resulting in signal loss."

A scenario in which a high gain preamp would have useful application would be where all signals in the air are predicted to have NM (noise margin) values in the teens or lower. Also, the antenna chosen is the highest performance available and it's mounted in a location that actually has receivable signal present. If a person hopes to use a small antenna and a high gain preamp, they should be prepared for disappointing results.

Reliable reception starts at the antenna (using the correct one), it's location and aim. Amplification of a poor quality signal does not improve the quality of the signal, any more than a pump can clean dirty water. That said, in the few situations that call for a high gain preamp, I can think of three options to consider...


Antennas Direct PA-18

Channel Master CM-7777

Kitztech KT-500
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If the well is dry and you don't see rain on the horizon, you'll need to dig the hole deeper. (If the antenna can't get the job done, an amp won't fix it.)

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Old 2-May-2015, 9:55 PM   #3
Jason l
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Nice thanks grounder mast any body use the kt 500? I'm really more interested in RESULTS. For educated guesses are just that. So if your antenna gets week signal on some stations???? My winegard 8275 29 db gain. Increases signal and ads channels.so anyone else have simular results. I have antennas with winegard preamps antenna craft preamp one without amp. I admit one without amp works but 9 of the 38 channels only work rarely real channel 7 ;44 ; 45. I tried and channel master Titan 2 and it worked no better than antenna without preamp didn't make antenna worse or better I was told from channel master I should not be using high gain. My reply was should not isn't in my vocabulary....... Lol. But seriously the 29 db gain works great is it not considered high gain. What works! Theory or reality or I guess what have you tried. I do have some close stations but I don't aim my detectional antenna at it I iam it of axis towerd furthest station.thanks for reply I will try a kt 500 next try.other two say no to Titan 2 antenna direct don't seam high enough
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Old 17-May-2016, 4:04 AM   #4
kenj66
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I have been using the Channel Master CM-7777 for a year now and it has been a stellar performer. It is the only pre-amp on the market, AFAIK, that claims a 30 db gain. I happen to need that kind of gain and it seems to perform properly with an Antennas Direct 91XG even though I have a TV transmitter 90 degrees off axis 5 miles away and a cell repeater a block away.

I'm posting here because I received a new product notice from Channel Master showing a redesigned pre-amp CM-7777HD which now includes a low-pass filter to eliminate interference from cellular telephone signals above 800 MHz. They also now have a separate in-line low-pass filter to retrofit existing installations.

Ken
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Old 17-May-2016, 5:01 PM   #5
ADTech
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Based on the CM7777 samples I have here, one purchased in the fall of 2012 and one in the fall of 2015, it appears that CM has changed the internal design of the 7777 by adding additional inter-stage attenuation to reduce overloading. This newer sample showed a total gain of about 24 dB instead of the advertised 30 dB.

I emailed CM about it since the product no longer matches their marketing specs but I never received any response. Go figure...
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Old 17-May-2016, 5:49 PM   #6
kenj66
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I was warned about the gain being too high and problems with adjacent transmitters overloading the unit. I also had a concern about the durability and rain getting into the innards. I have no problems in those ways - yet. The photo of the new model implies a complete redesign. It looks like it has a metallic housing now - perhaps more weather proof? The low-pass filter is a good idea but 4 db less gain? Ouch! Once in a while my channel 5 breaks up.
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Old 17-May-2016, 6:05 PM   #7
ADTech
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More gain is RARELY "better". More gain is only needed when there are additional insertion losses in the distribution system that must be overcome.


Consider this scenario:

Location where all signals are weak to moderate.
50 of RG6 and a 2 port splitter, worst case insertion loss of around 7 dB.
Install a 15 db preamplifier and everything works.
Install a 30 dB preamp and everything still works.
The TV tuner's don't care about the extra signal power as long as it's not too much and that the amplifier hasn't introduced new distortion into the signal.
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Last edited by ADTech; 17-May-2016 at 6:58 PM.
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Old 26-May-2016, 4:12 AM   #8
eggman531916
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I'm using an Antenna Craft 10g222 pre-amp. Works so well that I bought a second as a back up just in case the one I'm using fails for whatever reason. It's suppose to be 29 dB amplification. I don't know if it is or not, but it definitely helps me lock on to some channels I can't get without it. It looks like it may have been discontinued. Makes me glad I bought the second one.
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Old 6-Dec-2016, 6:51 PM   #9
davodavo
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My amp results/comparison

I own both the KT500 and the Channel Master 7777, plus a couple of other "high gain" amps from Radio Shack and no-name-Chinese mfr. I have no way of calibrating the actual gain and noise levels achieved, just doing A/B comparisons in real time.

My signal environment is "nothing" (seriously, no transmitters of any kind) within 25 miles, nothing over 300 kW within 50 miles...and then, at 60 miles there's 10+ megawatts (San Francisco). I have stacked Yagis pointed right at the signal...

Despite Channel Master's warning, there are no signs of the 7777 overloading (same with all the other amps). And of the amps I have, it has the best gain (==most channels, least pixelation). It is very solidly constructed and its only real downside is no gain control (==danger of overload). It's also cheap ($80 on Amazon). The Kitz is more $$, but it has three advantages: gain control, overload indicator, and much better warranty (and, I suspect, better than CM for reliability).

Last edited by davodavo; 6-Dec-2016 at 6:58 PM.
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